A 4-inch refractor, about 100 mm, is used for lunar photography, planetary photography and astrophotography; often it simply stays on the mount. With the TG-R4 from Telegizmos, a cover for a 4-inch refractor, you keep dust, dirt and moisture out of the tube, the focus mechanism and the viewfinder.<\/p>\n\n\n\n
The cover is intended for Refracting telescopes<\/a> With an opening of about 100 mm. If there is a camera or auto-guide attached, you will count that in your measurements.<\/p>\n\n\n\n Measure the refractor, including the dew cap, diagonal and viewfinder, and compare that with the dimensions of the case. Put the lens cap on the objective before you put the case over it, and let the telescope dry first after a wet night.<\/p>\n\n\n\n If you only want to protect the lens, there is the protective cap for the lens<\/a> from a 4 inch refractor. A dew point during observation helps rainbow band for 4 inch telescopes<\/a>.<\/p>","protected":false},"excerpt":{"rendered":" Telegizmos cover for a refractor of about 100 mm, to keep the tube, focus and viewfinder clean between two sessions.<\/p>","protected":false},"featured_media":113706,"comment_status":"open","ping_status":"closed","template":"","meta":{"_acf_changed":false},"product_brand":[3296],"product_cat":[3154,504,56],"product_tag":[],"class_list":["post-113707","product","type-product","status-publish","has-post-thumbnail","product_brand-telegizmos","product_cat-bescherm-hoezen","product_cat-draagtassen","product_cat-telescoop-accessoires","first","instock","taxable","shipping-taxable","purchasable","product-type-simple"],"bundled_by":[],"bundle_stock_status":"instock","bundle_stock_quantity":null,"bundle_virtual":false,"bundle_layout":"","bundle_add_to_cart_form_location":"","bundle_editable_in_cart":false,"bundle_sold_individually_context":"","bundle_item_grouping":"","bundle_min_size":"","bundle_max_size":"","bundle_price":[],"bundled_items":[],"bundle_sell_ids":[],"acf":[],"jetpack_sharing_enabled":true,"jetpack-related-posts":[{"id":113691,"url":"https:\/\/www.telescoop.nl\/en\/beschermhoes-voor-5-inch-refractor-tg-r5-telegizmos\/","url_meta":{"origin":113707,"position":0},"title":"Protective case for 5 inch refractor TG-R5 | Telegizmos","author":"Info telescoop","date":"09-10-2026","format":false,"excerpt":"Telegizmos cover for a refractor of about 127 mm, to cover the tube, focuser and viewfinder if you are not observing.","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/12199_1.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/12199_1.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/12199_1.jpg?resize=525%2C300&ssl=1 1.5x"},"classes":[]},{"id":113723,"url":"https:\/\/www.telescoop.nl\/en\/beschermhoes-voor-4-inch-refractor-op-eq-montering-t3-r4-telegizmos\/","url_meta":{"origin":113707,"position":1},"title":"Protective cover for 4 inch refractor on EQ mounting T3-R4 | Telegizmos","author":"Info 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refractor, to keep the tube, focus lens and viewfinder clean and dry when the telescope is in use.","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/12193_1.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/12193_1.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/12193_1.jpg?resize=525%2C300&ssl=1 1.5x"},"classes":[]},{"id":113695,"url":"https:\/\/www.telescoop.nl\/en\/beschermhoes-voor-6-inch-refractor-tgr-6-telegizmos\/","url_meta":{"origin":113707,"position":3},"title":"Protective cover for 6 inch refractor TGR-6 | Telegizmos","author":"Info telescoop","date":"09-10-2026","format":false,"excerpt":"Telegizmos cover for a refractor of about 150 mm, so you can set it up between two sessions and let it 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